Fountain pen



Patented May 1, 1923.

tain Pens, of which the following is a speci-` Y vation of a penembodying my-improvement,

f 'i Figure Figure OLIVER MITCHELL, or ianooKLIiv'ia,iviiissiioiusn'rtrs.

' FOUNTAIN PEN@ Application filed may `2i',

To @ZZ whom it may concern: v

Be itxknown that 1,'OLIviiR MITCHELL, ,a citizen;y of the United States, `residing at Brookline, in the county of Norfolk and State of Massachusetts, have invented certain new and useful ImprovementsinFouni'ication. v i v My inventionis' an improvement in (socalled) self-filling fountain pens.

inthe drawings :-l i I Figure 1 is a longitudinal sectional ele` vation of the upper'end of a pen embodying my improvements, showing the piston at the upperor'rearend o f its stroke; n

Figure 2 is a longitudinal sectional elesliowing'vthepiston at` the other end of its stroke; Y i f Figure 3 is a cross-section on line 3 3 of Fig. 1; i

4 is a cross-section on line 4-4 of Fig.' 2; t

figure 5 is a perspective of the disk 7; Figure 6 shows an alternative valve construction; f

` 7 is a section on line 7-7 of Fig..,6. As shown in the drawings, 1 is a fountain carrying at oney end an ink feed bar, 2, sup? porting in'` proper position apen, 3, as' is customary, and 4at the other end a gland, 4,

shaving a central p'erforation 41. Within the barrel, and mountedl longitudinally and preferably axially thereof, is a pipe 5, communicatingA with an aperture 51, passing through the feed bar 2, to the air. Mounted .at the upper end of the pipe 5; and prefer- 'tionally `fitting the interior vof the cylinder.

The disk 7, has an aperture, 71 therethrough, through which passes one end of a hollow ended rod, 8, which also passes through the perforation 41 in gland A4. This hollow end of rod, 8, has a side aperture, 81, and its free end, is open at 82. The rod 8 is also provided with two stops, 83 and 84, above and below the disk 7, respectively and, at its outer end equipped with a suitable finger piecef85. y

The operation is as follows: The parts being assembled and positioned as in Fig. 1, it is apparent that the interior of the fountain, l, is in communication with the interior the cylinder.

i922. vserial No..1564,i213.

of the cylinder6, boeneaththedisk through-, "i

the apertures 81 and 182 .ofthe rodf 8 which passes through aperture 71 in Idisk 7. The` disk is frictionally engagedwith theinterior of the cylinder 6,- andupon prelimi-` nary inward movement ofthe rod 8 from the position show-n in Fig. 1, the diskwillremain stationary, the rod 8 kmoving'through the disk until stop 83 contacts with the up-v per surface of the disk`7, the aperture 81 loe-y ing carried within the disk and closed by this movement of rod 8.@ L Further movement of rod 8 will carry disk 7 to theposition shown in Fig..2, expelling"- ,all' air 'in the cylinderf6, through pipe 5 andy aperture 5,1,` in theffeed bar, air passing v`into j cylinder 6 at the uppery end from the foun v ',tainl, behind tliedisk 7, thusfattenuating the air in fountain 1 and causing-an influx of air through theinkvfeed fissure 52, or, if fthe lower end of thelfountaingi's submerged in ink, causing an inflow of inkthrough ink l feed fissure 52., Y- Upon` a lreversal lof the movement of rod 8 the -preliminary movementof the rod8 vfrom the position shown in Fig.'2, the disk-frictionally engaging the` walls of cylinder 6, willremain stationary,

the rod l8 moving through the vdisk until".k

stop 84 contactsgwith'theunder surface of thedisk 7, the yaperture`-81 being carried opened by .this relative movement of rod and the aperture v81, hollow end ofjrod Sand aperture 82. Further movement of rodfbackl .to thev position shmvnI in-Fig..1,.will causek v -air 'above thefdisk to ,shiftthrough-the pasi sage through" the disk, tothe interior of the ka conical member 86, lwhich on `forward, movement of rod 8 closes the aperture 71 inV disk, thus .opening communication from above the disky to @below the fdisk through disk 7, andupon rearward movement of rod 8, opens aperture 71, the movement of the `iod bringing a spider, 87, against vthe surface of disk 7 to carry it to theopen end of The effect is that on the forward movement ofprod 8'the disk is closed to the passage of air and pushes all air trapped in the cylinder through pipe i ture 71`is open for the free passage of air 0n l rearward movement of vthe rod 8 the apere5 l above the upper surface vofthe disk and from one side of the disk to the other, the spider offering no resistance to air passage. The forward end, 88, of rod 8 between the conical member 86k and spider 87, is of reduced size and does not'fill aperture 71.

During the above described operation of expelling air no expelling pressure is put upon the contents of the fountain, but upon lthe contrary, during the operation the air innthefountainz is= -attenuated- During the upward movement of the rod S the: disk` valve eoi'npressesno air above it and attenuatesnolair beneath 1t, since the a-irpassage y throughithe disk renders the disk inoperative as a compressing element When the passage islopen; v

Ittivill be observed that theystroke of thev pumping element is, comparatively to the length ofi the'L barrel, short, and thatthe pum-p 'is effectivepro tanto, .even when th'e stroke is not fully completed vin eitherdirection'the result being thata series of short strokesfnoves vthe. same# volume of air'that would lbe movedA byk a single longstroke` in a long cylinder, thus.` through the use of a inderbeing in communication, through the closed end oflthe cylinder,v the cylinder having an opening at its rear end; a rod hollow at its frontend, passing through the gland and into the rearend ofthe cylinder, its inner hollow7 end opening' into'vthe cylinder and having ar sidev aperture; a,A pair of' stops mounted'up'onthefrodi a disk, mount# ed upon the rod between-the stops and frictionally engaging Ithe inner Walls ofthe cylinder, all organized as described; to cause the air-passage through-the rod lto lbe alter-v nately opened and closed bythe,v reciprocation. ofthe rod, as and for the vpurpose described.

2. In a fountain p en,..a fountain', carrying a feed bar and a pen at vits front end; a gland-,closing the rear end of the fountain; a pipe, Within the fountainfand arranged longitudinally,thereof, opening Without the fountain at the front end; a cylinder closed at the front end, mounted'upon thefrear endy of the.pi pe, thepipe and interior of the cylinder being in communication, .through the` closed endiof -the cylinder, thecylinderhaw ing an opening at .its rear-end; a rod, pass-fv ing through the gland and. intozthereariendf of the cylinder; av valve-piston actuated byi the rod,\vithin the cylinder and frictionally engrg'aging the inner 'Walls` of 'the cylin'den: all

organized to cause an air passage throughv` the Valve PSOH to be alternatelyvopenedfand dosed will@ '1'@Cprocauonfr of the rod; as and' forthe purpose described...

ln a fountain. pen, the combination with `the fountain andffeed bar, .ofan'vaiiif pipe mounted longitudinally Within. the

fountain" and opening at' its: front ende through thel feed vbar fto the ailr and communicating at its rear end through the closed!V front end of Va cylinder, .with thefinteriorzof the cylinder; that cylinder having an open;-

ing ut'its rear 'endto the'interior off'the fountain; a gland in the rear end offthie 'fountain an actuating rod passing Athrough they gland and into lthe interioriofthefcylin der; a Valve-piston With-in the cylinder, and? actuated by thevrod.' l j hln fa fountainl pen,. the combination 'With the fountain, offa cylinder, Withinfithe fountain,y andjhavinganv opening latfone-'endE to the interior of'thefountain/andv at-'th'e'w other end an open-ingqto the'V atmosphere; gland in theV rear end ofthe fountain; 'ansi actuating rod lpassing through thei gland l and into theI interior offthe cylinder.;` at valve-piston Within the cylinder and"actu-n Signed at'Bostoin Massachusetts, this 26th# day `of May, 1922.

oLrvnnLMrreH-Ennl 

